The investigation of litter decomposition and annual litterfall in beech, fir, fir- beech stands in the Arit district of Bartin province

In this study, among the different stands (beech, fir, fir-beech), annual needle and leaf fall and the decomposition of these needles and leaves were investigated. Besides, some soil properties (texture, pH, organic C, total N etc.) and the litter amounts of the investigated stand types were also determined. For this purpose, from the buffer zone of the Küre Mountains National Park in the Arıt District, 15 sample plots out of each stand type were selected and soil samples were taken from those plots. For the determination of the annual litter fall, five litter traps were located in each stand type. For the analysis of the needle and leaf decomposition, needle and leaf samples of the last year were collected from the each stand type. 18 litter bags for each stand, totally 54 litter bags were placed in the field. These litter bags were taken from the field at the end of each 3 months period along the 21 months total research time.Annual litter fall are 4245 kg ha-1, 2935 kg ha-1 and 3510 kg ha-1, in the beech, fir and fir-beech stands respectively. Remaining percentage of initial mass are 24.3%, 36.1% and 27.6% in the beech, fir and fir-beech stands respectively. The decomposition constant, ?k? values of needles and leaves are -0.159, -0.254 and -0.184 in the beech, fir and fir-beech stands respectively. According to variance analysis results, the soils of the stands differ about 5% at significance level from the point of some properties (moisture, organic C, silt, pH, grain density and Corg/Ntotal ratio).According to the results of the study, in the similar habitat conditions, the initial chemical composition of the needle and leaves (especially N, lignin and lignin/N) is the most significant factor which influences the decomposition and mass reduction. Also, the pH of soils value possibly affects the decomposition.Key Words: Beech, Fir, Fir-Beech, Needle, Leaf, Decomposition